Farrokh Alemi Ph.D.

Defining Probability

ElementEvent

Definition

Universe of possibilitiesVenn diagram

Definition

What is probability?All possible

events

What is probability?All possible

events

Event A

What is probability?

Probability of A =

What is probability?

What is probability?

Law of Large Numbers

Law of Large Numbers

Law of Large Numbers

Law of Large Numbers

Law of Large Numbers

Law of Large Numbers

More Observations

Less Error

Range of Probability

Odds

Odds

Odds

Odds

Odds

Odds

Odds

Odds

Odds

Probability as Opinion

Probability as Opinion

Axiomatic Definition of Probability

1. At least one event must happen

Axiomatic Definition of Probability

2. Probability is greater than or equal to zero

Axiomatic Definition of Probability

3. P(complement) is one minus P(Event)

Axiomatic Definition of Probability

4. P(two mutually exclusive events) is sum of each

Axiomatic Definition of Probability

Opinions Like Probabilities

On a scale from 0 to 100, where 100 is for sure, how certain are you that medication errors will occur in next visit?

Probability As Strength of Belief

Context for Study of Belief

Probability is the count of event divided by count of all possible events

Take Home Lesson

In examining wrong side surgeries in our hospital, what are the elements, events and the universe of possibilities? Draw the Venn Diagram

Do One